28215648 has 144 divisors (see below), whose sum is σ = 88194960. Its totient is φ = 8773632.

The previous prime is 28215619. The next prime is 28215653. The reversal of 28215648 is 84651282.

28215648 is a `hidden beast` number, since 2 + 8 + 2 + 1 + 5 + 648 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a super-3 number, since 3×28215648³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 249640 + ... + 249752.

It is an arithmetic number, because the mean of its divisors is an integer number (612465).

Almost surely, 2^28215648 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28215648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44097480).

28215648 is an abundant number, since it is smaller than the sum of its proper divisors (59979312).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28215648 is a wasteful number, since it uses less digits than its factorization.

28215648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166 (or 135 counting only the distinct ones).

The product of its digits is 30720, while the sum is 36.

The square root of 28215648 is about 5311.8403590469. The cubic root of 28215648 is about 304.4364690676.

The spelling of 28215648 in words is "twenty-eight million, two hundred fifteen thousand, six hundred forty-eight".